A typical liquid crystal display generally includes a display panel and a backlight module for illuminating the display panel. The backlight module can be classified into non-scanning and scanning backlight module. A non-scanning backlight module illuminates the display panel continuously while the display panel is turned on, but a scanning backlight module is switched on and off alternatively during a period of time while the display panel is turned on. The scanning backlight module includes a plurality of light emitting diodes (LEDs) arranged in a matrix array, which are switched on and off row by row so as to define a scanning effect for preventing the images between two frames of the display panel from image sticking.
Referring to FIG. 6, this shows a cross-sectional view of a backlight module 100 for a liquid crystal display. The backlight module 100 includes a reflective frame 2, a substrate 4, a plurality of red LEDs 8, a plurality of green LEDs 10, a plurality of blue LEDs 12, and a diffuser 14. The red, green, and blue LEDs 8, 10, 12 emit red, green and blue light beams respectively. The substrate 4 includes a plurality of partitions 6, and a plurality of slits 16 between the partitions 6. A cross section of each partition 6 is similar to a shape of a triangle.
The substrate 4 is located on the reflective frame 2, and the red, green, and blue LEDs 8, 10, and 12 penetrate through the slits 16. Light beams emitted from the LEDs 8, 10, and 12 are confined between two adjacent partitions 6. Each row of LEDs between two adjacent partitions 6 includes a plurality of the red, green, and blue LEDs 8, 10, and 12. Each of the partitions 6 and the substrate 4 is made from or coated with reflective material, such as silver. Therefore, the light beams emitted from the red, green, and blue LEDs 8, 10, and 12 can be reflected and concentrated between the adjacent partitions 6, and then almost all the light beams are reflected by the substrate 4 and the partitions 6 and enter the diffuser 14. The red, green, and blue LEDs 8, 10, and 12 in the same row are switched on or off together.
Along with the increasing size of the liquid crystal display, the size of the backlight module and the partitions used therein also increases. The partitions having larger size are liable to warp due to being pressed by the diffuser 14, thus, the quality of the liquid crystal display is decreased.
Accordingly, what is needed is an LED, a backlight module and a liquid crystal display configured to overcome the above-described problems.